JP3538479B2 - Double mass dynamic damper and drive axle with dynamic damper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double mass dynamic damper having two sub-vibration systems tuned to different frequency ranges, and a drive axle with a dynamic damper equipped with the double mass dynamic damper.

[0002]

2. Description of the Related Art Among vibrating bodies in various mechanical devices and the like, as a kind of a vibration isolating device for reducing vibration of a vibrating body having an axial form such as a shaft, an arm, and a flow pipe, in particular,
Conventionally, JP-A-2-62442 and JP-A-2-2-1
As disclosed in, for example, Japanese Patent Application Laid-Open No. 90641, there is known a dynamic damper having a structure in which a cylindrical mass member extrapolated to a vibrating body is elastically supported by the vibrating body by a supporting rubber.

[0003] By the way, as is well known, such a dynamic damper can exert an effective anti-vibration effect against vibration in a frequency range corresponding to its natural vibration frequency. In order to obtain the vibration reduction effect, adjust the mass of the mass member and the spring constant of the supporting rubber so that the natural vibration frequency can be adjusted as accurately as possible in accordance with the vibration frequency for the purpose of preventing vibration in the vibrating body. Need to tune.

However, in the dynamic damper having the conventional structure as described above, the natural vibration frequency can be set to only a single frequency range, so that the frequency range in which the effective vibration damping effect is exhibited is narrow. In particular, there is a problem that it is difficult to obtain an effective anti-vibration effect when there are plural types of vibration inputs.

When the vibration acceleration of the vibrating body changes, for example, as in the case of a driving axle of an automobile, in which the exciting force changes greatly depending on the driving conditions, etc., the mass member of the dynamic damper changes. When the amplitude changes, the spring constant of the supporting rubber changes, and the natural vibration frequency itself of the dynamic damper shifts, so that the anti-vibration effect against the target vibration may not be effectively exhibited. It was.

[0006]

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to exhibit an effective anti-vibration effect for input vibration in a wide frequency range. To provide a dynamic damper having a novel structure.

Further, the present invention provides a dynamic damper having a novel structure in which the shift of the natural frequency is suppressed even when the vibration acceleration of the vibrating body changes, and a stable vibration damping effect is exhibited. It is also the purpose.

[0008]

In order to solve such a problem, a feature of the first aspect of the present invention is that a cylindrical first body extrapolated to a shaft-shaped vibrator is provided. A first damper mechanism for elastically supporting the mass member with the first supporting rubber with respect to the vibrating body, and a cylindrical second mass member extrapolated to the shaft-shaped vibrating body; A second damper mechanism elastically supported by the second support rubber is tuned to different frequency ranges, and the first support rubber and the second support rubber are
Connected integrally at their axially opposed tips
To, while providing a connecting rubber for connecting because Shi serially not integrated in the axial direction, a pre-Symbol each axial facing surface of the the first mass member second mass member elastically, the first of the support rubber and said second support rubber and brought respectively interposed at least a portion between the axis-perpendicular direction facing surface of the the first mass member and said second mass member and the vibrating member, the compression /
Forming a tensile deformation portion, and furthermore,
Extending in the circumferential direction on at least one of the peripheral surface side and the outer peripheral surface side
By forming the groove portion, the perpendicularity between the first mass member and the second mass member is greater than the support spring constant in any direction perpendicular to the axis of the first support rubber and the second support rubber. A double mass dynamic damper in which the shear spring constant of the connecting rubber due to relative displacement in the direction is set small.

Further, in the double mass dynamic damper according to the first aspect of the present invention, the first support rubber and the second support rubber have axially opposite side portions, respectively.
And extend inclining radially inward toward the outside in the axial direction.
Tapered cylindrical portion, and the extension tip side of this tapered cylindrical portion
Inner peripheral surface, may be the mounting surface with respect to the outer peripheral surface of said vibrating body.

Further, a feature of the second aspect of the present invention is that a cylindrical first mass member extrapolated to a shaft-shaped vibrating body is firstly moved with respect to the vibrating body. A first damper mechanism elastically supported by the supporting rubber, and a cylindrical second mass member extrapolated to the shaft-like vibrating body elastically supported by the second supporting rubber with respect to the vibrating body. And a second damper mechanism tuned to different frequency ranges, and the first support rubber and the second support rubber are attached to their axially opposed tips.
And connected integrally, and integrated in series in the axial direction.
Because, before Symbol while each axial facing surface of the the first mass member second mass member provided connecting rubber for elastically connecting said vibration and said first mass member and the second mass member between the axis-perpendicular direction opposing surfaces of the body, to form a gap extending continuously in and circumferentially over the entire axial length of said first mass member and said second mass member, said first support While preventing pure compression deformation of rubber and the second support rubber,
A groove extending in the circumferential direction on at least one of the inner peripheral surface side and the outer peripheral surface side with respect to the connection rubber which is an integral axial connection portion of the first support rubber and the second support rubber. By providing, the first mass member and the second mass member relative to each other in the direction perpendicular to the axis than the support spring constant in any direction perpendicular to the axis of the first support rubber and the second support rubber. A double-mass dynamic damper in which the shear spring constant of the connecting rubber due to displacement is set small.

Further, in the double mass dynamic damper according to the first and second aspects of the present invention, both of the connecting rubbers are caused by relative displacement of the first mass member and the second mass member in a direction perpendicular to the axis. shear spring constant: the k _3, wherein the first support rubber and said second direction perpendicular to the axis of the support spring constant of the supporting rubber: ratio _{k 1, k 2: k 3} /
It is desirable that k ₁ , k ₃ / k ₂ be set to be と or more.

In the double mass dynamic damper according to the first and second aspects of the present invention, both are generally mounted on portions of the vibrating body whose outer diameter is substantially constant. The inner diameter of each of the first mass member and the second mass member is set to be larger than the outer diameter of the vibrating body by a predetermined size, and the axial direction of the first mass member and the second mass member The first support rubber and the second support rubber are formed so as to extend from both side portions inclining inward in the radial direction, respectively.

Furthermore, the third aspect of the present invention according to claim 6, a pair of drive axles for transmitting a driving force to the left and right sides of the drive wheels of the vehicle, with respect to the shorter driving axles of the axial length A drive axle with a dynamic damper, to which the double mass dynamic damper according to the first aspect of the present invention is attached, is characterized.

Further, the fourth aspect of the present invention according to claim 7,
The double-mass dynamic according to the second aspect of the present invention according to claim 3, wherein a driving axle having a longer axial length among a pair of driving axles that transmit driving force to driving wheels on both left and right sides of the vehicle is provided. It is characterized by a drive axle with a dynamic damper equipped with a damper.

[0015]

In the double mass dynamic damper according to the first and second aspects of the present invention, each of the two mass dampers has two damper mechanisms tuned to different frequency ranges. The vibration damping effect of the mechanism makes it possible to obtain a vibration damping effect that is effective for vibrations in a wide frequency range as compared with a conventional dynamic damper having only a single damper mechanism.

In the first and second double mass dynamic dampers according to the present invention, both the vibration of the first mass member in the first damper mechanism and the second mass member in the second damper mechanism are provided. And the like interfere with each other via the connecting rubber, so that the dependency of the spring constant of the spring component in the first damper mechanism and the second damper mechanism on the excitation force or the vibration acceleration is suppressed. As a result, even when the vibration acceleration of the vibrating body changes, the change in the natural vibration frequency of each damper mechanism is suppressed, and the desired vibration damping effect can be stably obtained.

Particularly, in the double mass dynamic damper according to the first aspect of the present invention, since the compression / tensile deformation portions are formed in both the first support rubber and the second support rubber, a relatively large spring is used. There is an advantage that it is easy to tune the natural frequencies of the first and second damper mechanisms to a high frequency range by setting a constant. In addition, if a groove is provided in the axial connection portion between the first support rubber and the second support rubber, it is possible to easily and sufficiently set the shear spring constant of the connection rubber.

[0018] Daburumasu formula Da according to the second aspect of the present invention
In the dynamic damper , since pure compression deformation is prevented in both the first support rubber and the second support rubber, it is necessary to set a relatively small spring constant and tune the natural frequency to a low frequency range. Is easy. Moreover, since the spring constant of the connecting rubber is suppressed by the groove provided in the axial connection portion between the first supporting rubber and the second supporting rubber, the spring constant of the first and second supporting rubbers is set small. Even in this case, there is an advantage that it is easy to set the shear spring constant of the connection rubber to be smaller than the spring constants of the first and second support rubbers.

Furthermore, the first and second double-mass dynamic dampers according to the present invention, wherein the shear spring constant of the connecting rubber: k ₃ and the spring constant of the first and second supporting rubber in the direction perpendicular to the axis: Ratio with k ₁ and k ₂ : k ₃ / k ₁ and k ₃
/ K ₂ is set to be 1/8 or more, the vibration of the first mass member in the first damper mechanism and the vibration of the second mass member in the second damper mechanism Can be more effectively generated through the connecting rubber of the first and second damper mechanisms, and stabilization of the natural vibration frequency in the first damper mechanism and the second damper mechanism can be more advantageously achieved.

Further, in the drive axle with the dynamic damper according to the third aspect of the present invention, an effective damper effect can be exhibited with respect to vibration in a relatively high frequency range which is likely to be a problem particularly on the short drive axle.

Further, in the drive axle with the dynamic damper according to the fourth aspect of the present invention, vibration in a relatively low frequency range which is likely to be a problem particularly on the long drive axle can be reduced.
An effective damper effect can be exhibited.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a double mass dynamic damper 10 as one embodiment of the first invention. The dynamic damper 10 has a substantially cylindrical shape as a whole, and is externally mounted on and mounted on a shaft-shaped vibrating body 12 such as a driving axle for an automobile, as indicated by a virtual line. The vibration of the vibrating body 12 is reduced by a dynamic vibration absorbing function (damper function).

More specifically, the dynamic damper 10
Is a first damper mechanism 18 including a first mass member 14 and a first support rubber 16, and a second mass member 2.
The second damper mechanism 24 including the first and second support rubbers 22 has a structure that is integrally connected to each other in the axial direction.

Here, each of the first mass member 14 and the second mass member 20 is formed of a material having a large mass such as a metal, and is larger than the outer diameter of the vibrating body 12 by a predetermined dimension. It has a thick cylindrical shape having an inner diameter.

Each of the first support rubber 16 and the second support rubber 22 is formed of a rubber elastic body made of an appropriate material. On the other hand, each is vulcanized and adhered.
Furthermore, each of the first support rubber 16 and the second support rubber 22 has a thin wall covering the inner peripheral surfaces of the first mass member 14 and the second mass member 20 in the axial center portion. Along with the rubber portion 26, both axial end portions are inclined from the axial end portions of the first mass member 14 and the second mass member 20 radially inward toward the outside in the axial direction. Outer tapered cylindrical portions 28, 28 are provided.
Then, the first support rubber 16 and the second support rubber 22
In each case, the mounting surfaces 30, 30 which are pressed against and fitted to the outer peripheral surface of the vibrating body 12 are formed by the inner peripheral surfaces of the tapered cylindrical portions 28, 28 at the extending distal end side, while the coating is performed. By making the inner diameter of the rubber portion 26 larger than the outer diameter of the vibrating body 12, the first mass member 14 and the second mass member 20 at the central portion in the axial direction of the first mass member 14 and the second mass member 20. Second mass member 20 and vibrating body 1
Annular space 32 extending in the circumferential direction between radially opposed surfaces of the annular space 32
Are formed respectively.

In this embodiment, the length of the gap 32 in the axial direction is shorter than the length of the first mass member 14 and the second mass member 20 in the axial direction. The first support member 16 and the second support member 16 are provided between the first mass member 14 and the radially opposed surfaces of the second mass member 20 and the vibrating body 12 at both axial portions of the second mass member 20, respectively. The compression / tensile deformation portions 34, 34 are formed by the interposition of the support rubber 22. Thereby, when the first mass member 14 and the second mass member 20 are vibrated and displaced in the radial direction with respect to the vibrating body 12, the first support rubber 16 and the second support rubber 2
2 of the first mass member 14 and the second mass member 20
Although the shear deformation mainly occurs in the portion located in the axially outward direction, the compression / tensile deformation portions 34 and 34 are exclusively subjected to the compressive / tensile deformation, thereby making the overall comparison. A large supporting spring constant is exhibited.

Further, the first support rubber 16 and the second support rubber 22 are formed on the tapered cylindrical portion 2 located on one side in the axial direction.
8 are integrally connected to each other at the tip end of
It has an integral structure made of a single rubber elastic body. That is, the first support rubber 16 and the second support rubber 22
Is formed as a single, integrally vulcanized molded product including the first mass member 14 and the second mass member 20. Note that, at the distal ends of the tapered tubular portions 28 located on the other axial side of the first support rubber 16 and the second support rubber 22, there are provided cylindrical extension tubular portions 36 extending in the axial direction, respectively. In addition, a belt groove 38 extending in the circumferential direction is provided on the outer peripheral surface of each of the extension cylindrical portions 36. The belt groove 38 is tightened by a belt member (not shown), thereby firmly fixing the position with respect to the vibrating body 12. It can be attached.

The connecting portion between the first support rubber 16 and the second support rubber 22 has an inner circumferential surface between the mounting surfaces 30 of the first support rubber 16 and the second support rubber 22. A groove 42 having a substantially wedge-shaped or semi-circular cross-section extending continuously in the circumferential direction is formed.

That is, in the dynamic damper 10 having such a structure, the first mass member 14 and the second mass member 20 are respectively attached to the first mass member 14 and the second mass member 20 when they are extrapolated and mounted on the vibrating body 12. The support rubber 16 and the second support rubber 22 allow the vibrating body 12 to be elastically supported so as to be displaceable in the radial direction, whereby the first vibrating body 12 as the main vibrating system as a sub-vibrating system is Thus, the damper mechanism 18 and the second damper mechanism 24 are configured. In addition, the first damper mechanism 18 and the second damper mechanism 24 have different natural vibration frequencies by appropriately setting the mass of each mass component and / or the spring constant of each spring component. The tuning is performed so that the vibrating body 12 can exhibit a vibration damping effect with respect to vibrations in different frequency ranges for the purpose of vibration damping. In the present embodiment, in particular, the first support rubber 16
And the second support rubber 22 each have a compression / tensile deformation portion 34, so that by setting a large spring constant in the direction perpendicular to the axis, for example, the axial The natural vibration frequencies of the first damper mechanism 18 and the second damper mechanism 24 can be easily tuned to a high frequency range of 200 Hz or more, which is likely to be a problem with a short drive axle. A drive axle with a dynamic damper according to the third invention can be advantageously realized.

In this case, the first damper mechanism 1
In the eighth and second damper mechanisms 24, each mass component is constituted by the first mass member 14 and the second mass member 20, while each spring component is constituted by the first support rubber 16 and the second support rubber. The first support rubber 16 and the second support rubber 22 are integrally connected to each other.
The connecting portion between the first mass member 14 and the second mass member 20 constitutes a connecting rubber 44 for elastically connecting the axially opposed surfaces of the first mass member 14 and the second mass member 20 to each other. The rubber 44 also affects the spring components in the first damper mechanism 18 and the second damper mechanism 24.

That is, the supporting spring constant of the first supporting rubber 16 in the direction perpendicular to the axis is k ₁ , the supporting spring constant of the second supporting rubber 22 in the direction perpendicular to the axis is k ₂ , the shearing spring constant of the connecting rubber 44 (the One mass member 14 and second mass member 20
(Referred to as the spring constant when shear deformation is caused by relative displacement in the direction perpendicular to the axis) is k ₃ , the dynamic damper 10 of this embodiment can be modeled as shown in FIG. is there.

The shear spring constant of the connecting rubber 44: k ₃
Is too large, the vibration state (displacement state) of the first mass member 14 and the second mass member 20 greatly interfere with each other, so that the resonance in the first damper mechanism 18 and the second damper mechanism 24 Since the states interfere with each other and become one, and the damper effect in each of the damper mechanisms 18 and 24 may not be effectively exerted, the shear spring constant of the connecting rubber 44: k ₃ Support rubber 1
It is necessary to set the spring constants of both the sixth support rubber 22 and the second support rubber 22 in the direction perpendicular to the axis: k ₁ and k ₂ . Here, in the present embodiment, both the first support rubber 16 and the second support rubber 22 are the compression / tensile deformation portions 34.
, The spring constant in the direction perpendicular to the axis: k ₁ ,
k ₂ can be set large, and in addition, a groove 42
Is formed, it is possible to set the shear spring constant: k ₃ of the connection rubber 44 to a small value, whereby the shear spring constant: k ₃ of the connection rubber 44 can be reduced by the first support rubber 16 and It is easy to set the spring constant in the direction perpendicular to any axis of the second support rubber 22 to be smaller than k ₁ and k ₂ .

In the dynamic damper 10 having such a structure, the spring constants of the respective spring components of the first damper mechanism 18 and the second damper mechanism 24 are equal to those of the first support rubber 16 and the first support rubber 16. Since it is affected not only by the second support rubber 22 but also by the connecting rubber 44, the change of the spring constant when the vibration state (vibration acceleration) of the vibrating body 12 changes is suppressed. Irrespective of the vibration state, the first damper mechanism 18 and the second damper mechanism 24 can effectively and stably exhibit a desired damper effect on vibration in a frequency range for vibration prevention. .

Incidentally, the dynamic damper 10 having the structure of the present embodiment is mounted on the vibrating body 12, and sensors are mounted on the first mass member 14 and the second mass member 20, respectively. By measuring the natural vibration frequencies of the first damper mechanism 18 and the second damper mechanism 24 in the case where the constant acceleration is applied at 1 G and the case where the constant acceleration is applied at 10 G in the perpendicular direction, respectively, The change of each natural vibration frequency was measured. The results are shown in FIGS. 3 and 4 and Table 1 below. In addition, the dynamic damper 10 having the structure of the present embodiment is cut along the groove 42 at the connecting portion between the first support rubber 16 and the second support rubber 22 so that the connection rubber 44 is substantially eliminated. One damper mechanism 18 and second damper mechanism 2
4 is used as a comparative example, and the first damper mechanism 18 and the second damper mechanism 24 are also similarly configured when the vibrating body is vibrated at a constant acceleration of 1 G and at 10 G. The natural vibration frequency was measured for each of the cases where the vibration was constant, and the results are shown in FIGS. 5 and 6 and also in Table 1 below.

[0036]

From these experimental results, it can be seen that, in the dynamic damper 10 having the structure of the present embodiment, in both the first damper mechanism 18 and the second damper mechanism 24, the amount of change in the natural vibration frequency with respect to the change in vibration acceleration. However, it is apparent that this is effectively suppressed with respect to the structure of the comparative example, and a stable vibration damping effect can be exhibited.

It should be noted that the first damper mechanism 18 and the second damper mechanism 24 are connected in a double mass structure as described above, and the mass members 14 and 20 of the respective damper mechanisms 18 and 24 are provided.
By providing the connecting rubber 44 for connecting the
It is clear from the above-mentioned experimental results and the like that the change in the natural vibration frequency with respect to the change in the vibration acceleration is suppressed and the stabilization of the vibration isolation characteristics (damper action) is achieved. It is inferred as follows.

That is, as shown in the model in FIG. 2, the spring components of the first damper mechanism 18 and the second damper mechanism 24 are all the support rubber 1
6, 22 as well as the connecting rubber 44, and the combination of the supporting rubbers 16, 22 and the connecting rubber 44 determines the spring constant of the spring component in the first damper mechanism 18 and the second damper mechanism 24. In other words, the first support rubber 16 and the second support rubber 22
Is directly deformed by vibrating the mass members 14 and 20 by vibrating force from the vibrating body 12, while the connecting rubber 44 is directly deformed by vibrating the mass members 14 and 20. The two mass members 14, 2
Since it is deformed by the relative displacement of 0,
The effect of the exciting force (ie, the dependency of the spring constant on the exciting force) is smaller than that of the supporting rubbers 16 and 22, and therefore,
With such connecting rubber 44, first and second support is a rubber vibration force dependent on 16, 22 reduces, is the amount of change of the spring formed <br/> portion of the spring constant is considered to be suppressed .

In addition, the first damper mechanism 1
The phase difference and the resonance magnification with respect to the exciting force in the eighth damper mechanism 24 and the second damper mechanism 24 can be expressed as shown in FIG. 7. For example, considering the resonance of the first damper mechanism 18, as shown in FIG. The first mass member 1
There is an area (shaded area in FIG. 8) where the second mass member 20 is displaced in the opposite phase with respect to 4. And
In the region displaced in the opposite phase, the opposite force by the second mass member 20 is applied to the first mass member 14 in the resonance state via the connecting rubber 44, and as a result, Since the spring constant of the spring component of the first damper mechanism 18 is increased, the relative displacement between the first mass member 14 and the second mass member 20 is increased as the vibration acceleration increases, and the connection is increased. Since the reverse force exerted on the first mass member 14 via the rubber 44 increases, the spring constant decreases as the vibration acceleration increases, and the natural vibration frequency of the first damper mechanism 18 decreases. Therefore, it is considered that stable vibration damping characteristics are exhibited. This can be similarly considered also at the time of resonance of the second damper mechanism 24, and the vibration acceleration due to the reverse force exerted on the second mass member 20 via the connecting rubber 44. Is decreased, the decrease in the natural vibration frequency of the first damper mechanism 18 is suppressed.

The first mass member 14 and the second mass portion
Rubber 44 at the time of relative displacement of the material 20 in the direction perpendicular to the axis
Shear spring constant: k_ThreeIs too small,
Mutual interference between one mass member 14 and second mass member 20
And the like in the first and second damper mechanisms 18 and 24.
The effect of stabilizing the natural vibration frequency becomes difficult to fully exert
There is a risk. Therefore, the shear spring of the connecting rubber 44 is set.
Number: k_ThreeAre the first support rubber 16 and the second support rubber
22: spring constant in any direction perpendicular to the axis: k ₁, K_Two
Also the ratio: k_Three/ K₁, K_Three/ K_TwoIs the value of
It is desirable to set so as to be 1/8 or more.

Next, FIG. 9 shows a dynamic damper 50 as one embodiment of the second invention. In the present embodiment, members and parts having the same structure as the dynamic damper 10 as the first embodiment of the present invention are respectively the same as those of the first embodiment of the present invention in the drawings. , The detailed description thereof is omitted.

In the dynamic damper 50 of this embodiment, the first damper mechanism 18 and the second damper mechanism 2
4 are formed over the entire length of the first mass member 14 and the second mass member 20 in the axial direction, so that the diameters of the first mass member 14 and the vibrating body 12 are increased. The first support rubber 1 is provided between the two opposing surfaces and between the second mass member 20 and the radial opposing surfaces of the vibrating body 12.
6 and the second support rubber 22 are not interposed, and the compression / tensile deformation portion is not formed.

Thus, the first mass member 14 and the second mass rubber 20 for elastically supporting the first mass member 14 and the second mass member 20 on the vibrating body 12 are provided with the first mass member 14 and the second mass member 20. At the time of vibration displacement of the second mass member 20 in the direction perpendicular to the axis, the occurrence of pure compressive deformation is avoided,
Shear and compression deformations are caused.

Therefore, the Dynami having such a structure is
Also in the damper 50, similar to the first embodiment,
Between the opposing surfaces of the first mass member 14 and the second mass member 20
Since the connecting rubber 44 is provided for connecting with each other,
Natural vibrations of the first and second damper mechanisms 18 and 24
The effect of stabilizing the wave number can be exhibited, and
In addition, in the dynamic damper 50 of the present embodiment,
Is pure compression in the first and second support rubbers 16 and 22.
Since the occurrence of deformation is avoided, the first support rubber
16 and the second support rubber 22 in the direction perpendicular to the axis.
Spring constant: k ₁, K_TwoIt is easy to set
And therefore, for example, of the left and right drive axles of a motor vehicle
200Hz or less, which is likely to be a problem with a driving axle with a long direction length
The first damper mechanism 18 and the second damper
Easy tuning of natural frequency of damper mechanism 24
The fourth invention of the present invention.
The drive axle with a dynamic damper according to the present invention is advantageously realized.
obtain.

Further, the dynamic damper 50 of the present embodiment
In the same manner as in the previous embodiment,
A groove 42 extending circumferentially on the inner peripheral surface of the central portion is formed.
Therefore, the first support rubber 16 and the second support
Spring constant of rubber 22 in the direction perpendicular to the axis: k₁, K_TwoSmaller
Even if it is set, the shear spring constant of the connection rubber 44: k _Three
Is the spring constant in the direction perpendicular to any of the axes: k₁, K_TwoYo
It is said that it is easy to set
You.

Although the embodiments of the present invention have been described above in detail, these are literal examples, and the present invention is not construed as being limited to only these specific examples.

For example, in the dynamic damper according to the first aspect of the present invention, since the compression / tensile deformation portion 34 can set the supporting spring constant of the first and second supporting rubbers 16 and 22 in the direction perpendicular to the axis, large. Connection rubber 44
The shear spring constant of Ru der can be easily set smaller than such supports spring constant.

In the dynamic damper according to the first aspect of the present invention, the inner peripheral surface of the coating rubber layer 26 of the first support rubber 16 and / or the second support rubber 22 is in close contact with the outer peripheral surface of the vibrator 12. In this way, the gap 32 is eliminated, and the compression / tensile deformation portion 34 is formed over the entire length of the mass member in the axial direction, or the covering rubber layer 26 is formed in the middle portion of the gap 32 in the axial direction. It is also possible to form the compression / tensile deformation part independently by closely contacting the outer peripheral surface of the first member.

Further, in the above embodiment, the groove 42 is formed on the inner peripheral surface of the connecting rubber 44. However, in the first and second dynamic dampers according to the present invention, such an inner peripheral surface side is provided. Instead of or in addition to the groove 42, FIG.
As shown in (1), it is possible to form a groove portion 46 extending in the circumferential direction on the outer peripheral surface side of the connection rubber.

Furthermore, the axially opposed surfaces of the first mass member 14 and the second mass member 20 need not necessarily be directly opposed in the axial direction.
It is also possible to set the inner diameter of the second mass member 20 larger than the outer diameter of the fourth mass member 20.

Further, in the above embodiment, the outer peripheral surface of the connecting rubber 44 is connected to the first mass member 14 and the second mass member 20.
Although the cross-sectional shape was substantially V-shaped, the diameter of which decreased toward the center from both sides in the axial direction with respect to the side. However, such a shape is not limited, and various types of tuning were performed when tuning to the target vibration-proof characteristics. Shapes may be employed, such as connecting rubber 44
It is also possible to form the outer peripheral surface of the cylindrical member into a cylindrical shape having a constant outer diameter.

The dynamic damper according to the first and second aspects of the present invention is not only a drive axle for an automobile, but also various shaft-like structural members such as various shafts and arms, and tubes forming fluid flow paths. In addition, any of those having a problem of resonance or transmission of vibration through the resonance itself can be advantageously applied as a dynamic vibration absorber.

In addition, although not enumerated one by one, the present invention
Based on the knowledge of those skilled in the art, various changes, modifications, improvements, and the like can be made, and unless such embodiments depart from the spirit of the present invention.
Both are included in the scope of the present invention,
Needless to say.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a dynamic damper as one embodiment of the first invention.

FIG. 2 is an explanatory view showing a dynamic model of the dynamic damper shown in FIG. 1;

FIG. 3 is a graph showing measurement results obtained by actually measuring the excitation force dependency of the natural vibration frequency for the first damper mechanism of the dynamic damper shown in FIG.

FIG. 4 is a graph showing measurement results obtained by actually measuring the excitation force dependency of the natural vibration frequency for the second damper mechanism of the dynamic damper shown in FIG.

FIG. 5 is a graph showing measurement results obtained by actually measuring the excitation force dependency of the natural vibration frequency for a first damper mechanism alone as a comparative example.

FIG. 6 is a graph showing measurement results obtained by actually measuring the excitation force dependence of the natural vibration frequency for a second damper mechanism alone as a comparative example.

FIG. 7 shows the dynamic damper shown in FIG.
5 is a graph illustrating a relationship between a phase difference with respect to an exciting force and a resonance magnification.

FIG. 8 shows a dynamic damper shown in FIG.
9 is a graph for explaining a phase difference at the time of resonance of the first damper mechanism.

FIG. 9 is a longitudinal sectional view showing a dynamic damper as one embodiment of the second invention.

FIG. 10 is an explanatory longitudinal sectional view showing a main part of a dynamic damper as another embodiment of the first and second inventions.

[Explanation of symbols]

10,50 Dynamic damper 12 vibrator 14 First mass member 16 First support rubber 18 First damper mechanism 20 Second mass member 22 Second support rubber 24 Second damper mechanism 32 void 34 Compression / tensile deformation 42, 46 groove 44 Connecting rubber

Continuation of the front page (72) Inventor Masaaki Hamada Komaki City, Aichi Prefecture Oita Kita-gaiyama 3600 Gezu Tokai Rubber Industries Co., Ltd. (56) References JP-A 2-221731 (JP, A) 62442 (JP, A) JP-A-8-28627 (JP, A) JP-A-7-208550 (JP, A) Japanese Utility Model Application No. 64-53542 (JP, U) Japanese Utility Model Application No. 3-25048 (JP, U) (58) Field surveyed (Int.Cl. ⁷ , DB name) F16F 15/12 F16F 15/02 F16F 7/10 B60K 17/22

Claims (7)

(57) [Claims] 1. A first damper mechanism for elastically supporting a cylindrical first mass member extrapolated on a shaft-shaped vibrating body by a first support rubber with respect to the vibrating body, and the shaft. A second damper mechanism for elastically supporting the cylindrical second mass member extrapolated to the vibrating body by the second supporting rubber with respect to the vibrating body is tuned to different frequency ranges. At the same time, the first support rubber and the second support rubber are held together at their axially opposed distal ends.
And body to articulation, while providing a connecting rubber for connecting because Shi serially not integrated in the axial direction, a pre-Symbol each axial facing surface of the the first mass member second mass member elastically The first support rubber and the second support rubber are interposed in at least a portion between surfaces of the first mass member and the second mass member and the vibrating body, respectively, in a direction perpendicular to an axis , compressive / tensile deformation portion is formed, to further the connecting rubber
At least one of the inner peripheral surface side and the outer peripheral surface side
By forming a groove extending in the circumferential direction, the first mass member and the second mass member are more than the supporting spring constant of any of the first support rubber and the second support rubber in the direction perpendicular to the axis. Characterized in that the shear spring constant of the connecting rubber due to the relative displacement in the direction perpendicular to the axis is set small. 2. An axially opposite side portion of each of the first support rubber and the second support rubber is directed outward in the axial direction.
A tapered cylindrical portion that extends inclining radially inward,
The inner peripheral surface of the extended distal end of the tapered cylindrical portion is
The double mass dynamic damper according to claim 1, wherein the double mass dynamic damper is a mounting surface with respect to an outer peripheral surface . 3. A first damper mechanism for elastically supporting a cylindrical first mass member extrapolated to a shaft-shaped vibrating body by a first supporting rubber with respect to the vibrating body, and the shaft. A second damper mechanism for elastically supporting the cylindrical second mass member extrapolated to the vibrating body by the second supporting rubber with respect to the vibrating body is tuned to different frequency ranges. At the same time, the first support rubber and the second support rubber are held together at their axially opposed distal ends.
And body to articulation, while providing a connecting rubber for connecting because Shi serially not integrated in the axial direction, a pre-Symbol each axial facing surface of the the first mass member second mass member elastically Between the opposing surfaces of the first mass member and the second mass member and the vibrating body in the direction perpendicular to the axis, over the entire length in the axial direction of the first mass member and the second mass member, and forming a gap extending continuously in a direction, integral of the first as well as preventing the net compressive deformation of the support rubber and said second support rubber, the second support rubber and said first support rubber By providing a groove extending in the circumferential direction on at least one of the inner peripheral surface side and the outer peripheral surface side with respect to the connection rubber serving as an important axial connection portion, the first support rubber and the second rubber are provided. Than any of the support spring constants of the support rubber in the direction perpendicular to the axis, the first Scan member and the second Daburumasu type dynamic damper, characterized in that by the axis-perpendicular direction of the relative displacement of the mass member is set smaller shearing spring constant of the connecting rubber. 4. An axially opposite side portion of each of the first support rubber and the second support rubber is directed outward in the axial direction.
A tapered cylindrical portion that extends inclining radially inward,
The inner peripheral surface of the extended distal end of the tapered cylindrical portion is
The double mass dynamic damper according to claim 3 , wherein the double mass dynamic damper is a mounting surface with respect to an outer peripheral surface . 5. The first support rubber and the second support having a shear spring constant: k ₃ of the connecting rubber due to a relative displacement of the first mass member and the second mass member in a direction perpendicular to the axis. Support spring constant of rubber in the direction perpendicular to the axis: k ₁ , k
Ratios to ₂ : k ₃ / k ₁ and k ₃ / k ₂ are both 1
The double-mass dynamic damper according to any one of claims 1 to 4 , wherein the dynamic damper is at least / 8. 6. The double-mass dynamic damper according to claim 1, wherein a driving axle having a shorter axial length among a pair of driving axles transmitting driving force to driving wheels on both left and right sides of the vehicle. A drive axle with a dynamic damper that is fitted. 7. A double-mass dynamic damper according to claim 3, wherein a drive axle having a longer axial length among a pair of drive axles for transmitting drive force to drive wheels on both left and right sides of the vehicle. A drive axle with a dynamic damper that is fitted.